Asbestos brake-band.



L. R. HOFF.

ASBESTOS BRAKE BAND.

APPLICATION FILED NOV. 5. 1909 Patented Dec. 19, 1911.

m 1 .w a a mw UNITED STATES PATENT OFFICE.

LOUIS R. HOFF, OF PATEBSON, NEW JERSEY, ASSIGNOB, BY MESNE ASSIGNMENTS, TO THE ASBESTOS BRAKE COMPANY, A. CORPORATION OF NEW JERSEY.

Asnns'ros nnnxnnmn.

Specification of Letters latent.

Patented Dec. 19, 1911.

To all whom it may concern: Be it known that I, LOUIS R. Horn, a citizen of the United States of America, residing at Paterson, county of Passaic, State of New Jersey, have invented certain new and useful Improvements in Asbestos Brake- Bands, of which the following is a specifica tion.

My apparatus relates to apparatus for checking the speed of revolution of rotating members of various mechanism, as in wheeled vehicles, hoisting machinery and the like, and comprises an improved flexible brake band adapted to be used as a facing for the ordinary metal brake band, and to bear upon the drum or other revolving member when the brake is set,

Heretofore such brake band facings have sometimes been made of hair felt or other animal or vegetable fiber, these being used to give evenness and regularity to the braking action, but these materials burn out and wear out rapidly when heavy brake pres-' sures are used, and do not have a sufliciently high retarding action. I have discovered that if such brake bands are faced with strips of woven asbestos fiberthe above recited difficulties are overcome in large art. In order to give the asbestos tape or and additional strength, I incorporate strands of fine wirein the warp in weaving same, as a metallic reinforcement.

The best form of apparatus embodying o ;s1ty cohesion. Any other combination illustrated in the accompanying sheet of my invention, at present knownto me, 1s

drawing, in which:

Figure 1 is a vertical section of one form of brake band and brake drum to which my invention has been applied. Fig. 2 is a cross section of one form of asbestos strip or band for use in such apparatus. Fig. 3 is another form, and F ig. 4 is a detail of one of the asbestos and wire strands used to form the warp.

Throughout the drawings, like reference by any suitable fastening means, 4, 4, and overlying the face of the metal band.

One form of double woven band is shown in cross section in exaggerated form in- Fig. 2. This band is composed of a series of war threads 9, 9, 9, etc. so interwoven with the woof threads that portions 10 and 11 of the woof combine with certain of the warp threads to forma facing forthe band. Portions 12 and 13 of the woof combine with other warp threads to form a back portion. Portions 14 pass in between the face and the back to form a stufling, and portions 15 of the woof intertwine with all the warp threads to bind the parts together in one integral structure. The warp threads are formed by twisting together a fine metal wire 9 and an asbestos thread 9", as shown in Fi 4, the wire forming a reinforcing meta 1e strand, practically surrounded by of d oil and suitable materials, or a dryig zfi alone may be used.

A articularl efiective impregnating materia is formed of the material, known as gilsonite dissolved in na htha. After impregnation the brake ban is exposed to the air and the na htha evaporates, leavin the gilsonite distri uted throughout the fa ric. This gilsonite not only makes the brake band impervious to moisture but adds to its friction creating qualities,

In operation the asbestos strip is fastened inside of the metal band, as shownin Fig. 1, and when the same is caused to grip the drum by movement of the lever 5, or equivalent means, a high degree of friction is developed between the metal drum and the asbestos, which .latter serves to promptly and evenly retard the speed of IGVOllltlOIl of the drum.

My invention finds a most useful application in the brake rigging of heavy motor cars.

Any other convenient form of holding means may be employed.

Among the advantages of my invention may be mentioned the high eoefiicient of friction of asbestos on metal which is much greater than that of metal on metal, or of animal or ve etable fiber on metal; the fact that asbestos ein a pure mineral substance will not burn an does not heat so rapidly as other fiber; and that it wears longer and does not disintegrate so readily under the abrasive and heating efi'ects of the brake action.

The particular forms of asbestos band shown are advantageous as possessing at lasting ualities on account of their t ickness, an also that compressibilit resulting from thickness which enables t e braking effect on the two wheels of a motor car to be approximately equalized even if the adj ustment of the two brake bands is not quite perfect. I

Of course other arrangements of textile fabric formed of asbestos might be employed and these asbestos strips can be used to advanta e in forms of brake ri ging other than t at here shown and descri ed.

The relative degrees of twist given to the asbestos and wire strands may be varied so as to cause one or the other to form the greater portion of the exterior surface or coat' of the strand.

Hav1ng,-therefore, described my invention, I claim:

1. A brake rovided with a liner comprising a layer o? asbestos fabric impregnated with a drying oil and having a wire reinforeement.

2. In a brake, the combination with a hold ing element of a la er of asbestos impregnated with drying oil and having wire reinforeement.

3. In a braking element, a plurality of lies of fabric composed of interwoven, astos coated wires, said plies being impregnatedwith a d ing oil.

4. I11 a brakm element, a plurality of plies giwire rein orofddasbetfitcs fabric lsaid me im re ae W1 rm 01. P mg p gn LOUIS a? OFF.

Witnesses:

A. G. Co'rrmo, J. E. ABEL-BERG. 

